Basics of Organic Chemistry

Jun 22, 2024

Basics of Organic Chemistry

Definition and Origin

  • Study of Carbon Compounds: Organic chemistry is the study of carbon and its compounds.
  • Millions of Compounds: There are millions of organic compounds.
  • Origins: Derived from living organisms.

Electrons and Bonding

  • Outermost Electrons: Electrons in the outermost shell are involved in bonding.

Functional Groups

  • Importance: Key to understanding properties and reactions of organic compounds.
  • Examples:
    • Alcohols
    • Carboxylic acids
    • Aldehydes
    • Ketones
    • Amines
    • Isocyanates

IUPAC Nomenclature Rules

  1. Longest Chain: Identify the longest carbon chain in the molecule.
  2. Substituent Positioning: Number the chain such that substituents get the lowest possible numbers.
  3. Multiple Functional Groups: Use prefixes/suffixes to denote functional groups; prioritize based on IUPAC rules.

Hybridization

  • Definition: Mixing of atomic orbitals to form new hybrid orbitals.
  • Types:
    • sp3 hybridization
    • sp2 hybridization
  • Sigma Bonds: Formed by head-on overlapping of orbitals.

Carbon Classification

  • Primary Carbon (1°): Attached to one other carbon.
  • Secondary Carbon (2°): Attached to two other carbons.
  • Tertiary Carbon (3°): Attached to three other carbons.
  • Example: Primary alcohols have the hydroxyl group (-OH) on a primary carbon.

Free Radicals

  • Definition: Species with unpaired electrons.

Electron Effects

  • Inductive Effect: Transmission of charge through a chain of atoms in a molecule by electrostatic induction.
  • Resonance: Delocalization of π-electrons in a molecule.

Nucleophiles and Electrophiles

  • Nucleophiles: Species that donate an electron pair (e.g., Cl⁻, Br⁻).
  • Electrophiles: Species that accept an electron pair.

Alpha, Beta, Gamma Carbons

  • Alpha Carbon: Carbon adjacent to a functional group.
  • Beta and Gamma Carbons: Subsequent carbons in the chain.

Reactions

  • Dehydration: Removal of water (e.g., catalyzed by ZnCl₂, KHSO₄).
  • Hydrogenation: Addition of hydrogen.
  • Halogenation: Addition of halogens (Cl, Br, I).
  • Oxidation and Reduction:
    • Oxidation: Addition of oxygen or removal of hydrogen (e.g., CrO₃, PCC).
    • Reduction: Addition of hydrogen (e.g., lithium aluminium hydride).

Summary

  • Understanding organic chemistry requires knowledge of bonding, functional groups, nomenclature, and different types of reactions and classifications related to carbon and its compounds.